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1.
Polymers (Basel) ; 16(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38543421

RESUMO

Polyvinylidene fluoride (PVDF) nanofiber mats have played a significant role in wearable electronic devices that have been in great demand in recent decades. Although manifold PVDFbased freely stacked or well-aligned nanofiber mats created via the electrospinning process have been demonstrated to achieve multisensory capabilities with high sensitivity and long detection range, rarely have any of them proved their ability with a stable process and accurate processing parameters. In this work, we successfully developed freely stacked and well-aligned PVDF nanofiber mats with diameters ranging from micrometers to nanometers, providing stable performance for wearable electronic devices. Through in-depth investigations into material preparation, electrospinning, and fiber collection processes, we revealed the relationship between the nanofiber morphology, ß-phase fraction, and piezoelectric output with various process parameters. Characterized by analytical methods, we have established a mature, reliable nanofiber mat fabrication system capable of mass-producing PVDF nanofibers with the required diameter and consistent properties. At 18 kV voltage and 60% RH humidity, the uniformity of the fiber diameter and ß-phase content was maintained in a favorable range. When the drum speed increased to 2000 r/s, the fiber orientation and ß-phase content increased. We assembled aligned PVDF nanofiber mats with conductive fabric in a flexible piezoelectric sensor that successfully monitored different body movements and produced an output voltage of 0.1 V. This study provides the necessary process parameters for the large-scale production of high-quality PVDF nanofiber mats and provides clear guidance for beginners in the field of nanofiber mat manufacturing.

2.
Ophthalmology ; 130(5): 542-550, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36642334

RESUMO

PURPOSE: Defocus incorporated multiple segments (DIMS) spectacle lenses were reported to slow myopia progression significantly in a randomized controlled trial (RCT). The study evaluated their effectiveness in clinical settings. DESIGN: Retrospective study. PARTICIPANTS: Patient records involving use of DIMS and single-vision (SV) spectacle lenses were collected from subsidiary hospitals of Aier Eye Hospital Group. METHODS: The spherical equivalent (SE), determined by subjective refraction, was adopted to assess the myopia progression. The strategy of propensity score matching (PSM) was applied to match the confounding baseline characteristics between the 2 groups. The effectiveness was calculated based on the difference of myopia progression of these 2 approaches. MAIN OUTCOME MEASURES: Change in SE. RESULTS: Three thousand six hundred thirty-nine patients with DIMS and 6838 patients with SV spectacles were included. The age of the patients was 6 to 16 years (mean ± standard deviation: 11.02 ± 2.53 years). The baseline SE was between 0.00 and -10.00 diopters (D) (mean ± standard deviation: -2.78 ± 1.74 D). After the PSM, data on 2240 pairs with 1-year follow-up and on 735 pairs with 2-year follow-up were obtained. Significantly slower progression was seen in the DIMS group at both the 1-year (DIMS, -0.50 ± 0.43 D; SV, -0.77 ± 0.58 D; P < 0.001) and 2-year (DIMS, -0.88 ± 0.62 D; SV, -1.23 ± 0.76 D; P < 0.001) subdataset. In the 1-year subdataset, 40% and 19% showed myopia progression of no more than 0.25 D for the DIMS and SV groups, respectively (chi-square, 223.43; P < 0.001), whereas 9% and 22% showed myopia progression of more than 1.00 D for the DIMS and SV groups, respectively (chi-square, 163.38; P < 0.001). In the 2-year subdataset, 33% and 20% showed myopia progression of no more than 0.50 D for the DIMS and SV groups, respectively (chi-square, 31.15; P < 0.001), whereas 12% and 29% showed myopia progression of more than 1.50 D for the DIMS and SV groups (chi-square, 65.60; P < 0.001). CONCLUSIONS: Although the magnitude was lower than that reported in the previous RCT, this large-scale study with diversity of the data sources confirmed the effectiveness of DIMS spectacles to slow myopia progression in clinical practice. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Assuntos
Miopia , Humanos , Criança , Adolescente , Miopia/terapia , Refração Ocular , Óculos , Progressão da Doença , Face
3.
Toxicol Appl Pharmacol ; 433: 115778, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34755645

RESUMO

Indoprofen is a non-steroidal anti-inflammatory drug, and has provided insights into treatment of spinal muscular atrophies; however, the treatment effect of indoprofen on sepsis and the precise underlying mechanism remain to be elucidated. This study was carried out to examine the inhibitory effect of indoprofen on high mobility group box 1 (HMGB1)-mediated inflammatory responses in vivo and in vitro. Intraperitoneal injection of indoprofen (20 or 40 mg/kg) at 8 h post-sepsis markedly improved the survival of BALB/c mice and ameliorated multiple-organ injury by blocking the inflammatory responses. In addition, indoprofen partially reduced the HMGB1 level in the serum and in the lung, as well as ameliorated pulmonary edema. Mechanistically, indoprofen potently inhibited the release of HMGB1 following stimulation by lipopolysaccharide (LPS) or polyinosinic:polycytidylic acid (poly I:C), and suppressed recombinant human HMGB1(rhHMGB1)-induced inflammatory responses. It was also found that indoprofen has both cyclooxygenase 2-dependent and -independent inhibitory effects on the proinflammatory effect of HMGB1 in THP-1 cells. Further, the drug reduced rhHMGB1-induced cell surface levels of toll-like receptor 2, toll-like receptor 4, and receptor of advanced glycation end-products in a concentration-dependent manner. Collectively, these data demonstrated that the anti-inflammatory effect of indoprofen in sepsis was associated with HMGB1-mediated inflammatory responses, thus offering a favorable mechanistic basis to support the therapeutic potential of indoprofen for the treatment of lethal sepsis or other inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Proteína HMGB1/metabolismo , Indoprofen/farmacologia , Mediadores da Inflamação/metabolismo , Pulmão/efeitos dos fármacos , Sepse/prevenção & controle , Animais , Inibidores de Ciclo-Oxigenase/farmacologia , Modelos Animais de Doenças , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Células RAW 264.7 , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Sepse/imunologia , Sepse/metabolismo , Transdução de Sinais , Células THP-1 , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
4.
Inflammation ; 43(3): 1157-1169, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32128658

RESUMO

Glutathione S-transferase Pi (GSTP1) was originally identified as one of the cytosolic phase II detoxification enzymes and was also considered to function via its non-catalytic, ligand-binding activity. Autophagy is a self-protective mechanism of the cell to remove unnecessary or dysfunctional components, which plays a crucial role in balancing the beneficial and detrimental effects of immunity and inflammation. However, little is known about whether and how GSTP1 mediates autophagy via inhibiting LPS-induced inflammatory response. Here, we show that LPS-induced autophagy and autophagic flux blockade in THP-1 cells in a concentration- and time-dependent manner. Further, we found that the autophagy activation inhibited the activation of inflammatory signaling pathway and the release of inflammatory factors. However, inhibition of autophagy by 3-methyladenine or chloroquine significantly reduced the anti-inflammatory effect of GSTP1. In addition, our findings provide evidence that GSTP1 regulates autophagy through PI3K-Akt-mTOR pathway and inhibits LPS-induced inflammation. Overall, the current study provides an important reference for future applications of GSTP1 in the treatment of inflammatory diseases.


Assuntos
Autofagia/fisiologia , Glutationa S-Transferase pi/biossíntese , Lipopolissacarídeos/toxicidade , Células THP-1/metabolismo , Autofagia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/prevenção & controle , Células THP-1/efeitos dos fármacos
5.
Front Immunol ; 11: 625542, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33603756

RESUMO

CREB binding protein (CBP), a transcriptional coactivator and acetyltransferase, is involved in the pathogenesis of inflammation-related diseases. High mobility group box-1 protein (HMGB1) is a critical mediator of lethal sepsis, which has prompted investigation for the development of new treatment for inflammation. Here, we report that the potent and selective inhibition of CBP bromodomain by SGC-CBP30 blocks HMGB1-mediated inflammatory responses in vitro and in vivo. Our data suggest that CBP bromodomain inhibition suppresses LPS-induced expression and release of HMGB1, when the inhibitor was given 8 h post LPS stimulation; moreover, CBP bromodomain inhibition attenuated pro-inflammatory activity of HMGB1. Furthermore, our findings provide evidence that SGC-CBP30 down-regulated rhHMGB1-induced activation of MAPKs and NF-κB signaling by triggering the reactivation of protein phosphatase 2A (PP2A) and the stabilization of MAPK phosphatase 1 (MKP-1). Collectively, these results suggest that CBP bromodomain could serve as a candidate therapeutic target for the treatment of lethal sepsis via inhibiting LPS-induced expression and release of HMGB1 and suppressing the pro-inflammatory activity of HMGB1.


Assuntos
Anti-Inflamatórios/farmacologia , Proteína de Ligação a CREB/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Proteína HMGB1/imunologia , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sepse , Animais , Proteína de Ligação a CREB/imunologia , Regulação para Baixo/imunologia , Humanos , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Sepse/induzido quimicamente , Sepse/tratamento farmacológico , Sepse/imunologia , Sepse/patologia , Células THP-1
6.
Cell Biol Int ; 44(1): 253-267, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31483551

RESUMO

Heat shock protein 27 (Hsp27) is a member of the small heat shock protein family expressed at high levels to protect cells against heat shock and other conditions of stress. Hsp27 has been indicated in the regulation of inflammation signaling pathway, and Hsp27 phosphorylation is vital for efficient control of host-defense response in early stages of lipopolysaccharide (LPS)-stimulated inflammation. The notion that CREB-binding protein (CBP) is involved in the regulation of two major transcription factors, nuclear factor-κB (NF-κB) and AP-1, suggests that CBP, as a coactivator protein, may also play an important role in the cellular response to inflammation. Here, we explored the mechanism underlying the regulatory relationships between Hsp27 and CBP in THP-1 cells, and found that phosphorylated Hsp27 was critical to the protein level of CBP. Furthermore, in exploring the signaling mechanisms underlying its action, we found that p38MAPK-MK2-Hsp27 regulated NF-κB via CBP, which acted as a multi-protein complex assembly scaffold. Finally, we demonstrated that phosphorylated Hsp27 reduced reactive oxygen species accumulation thereby significantly repressed LPS-induced excessive increase of CBP. Taken together, our data demonstrated that Hsp27, in its phosphorylation state, plays a critical role in controlling LPS-induced inflammatory response by modulating CBP.

7.
Sci Rep ; 9(1): 15105, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641190

RESUMO

The effects of sea salt aerosols (SSA) on cloud microphysical processes, precipitation, and upper troposphere/lower stratosphere water vapour in tropical cyclones were studied with the Weather Research and Forecasting with Chemistry model. Two numerical experiments were conducted: a control experiment (CTL) and an experiment with sea salt emission intensity one-tenth of that in the CTL experiment (CLEAN). Results show increased SSA concentrations, increased production rates of auto-conversion of cloud water to form rain, and increased accretion of cloud water by rain in the CTL experiment, leading to an increase in the precipitation amount. The peak value of precipitation is ~17 mm/h in the CTL experiment and ~13 mm/h in the CLEAN experiment, a difference of ~30%. The CTL experiment has more intense vertical movement in the eyewall and thus more water vapour is transported to the upper atmosphere, which promotes cloud ice deposition. This process consumes more water vapour, which makes the CTL experiment drier in the upper troposphere/lower stratosphere layer (altitude above 17 km). At 18-20 km altitude, the domain-averaged water vapour mixing ratio of the CTL experiment is ~0.02 ppmv lower than that of the CLEAN experiment. SSA have the effect of strengthening tropical cyclones and increasing precipitation.

8.
Inflammation ; 42(5): 1788-1799, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31201585

RESUMO

The aims of this study were to investigate the effect of Hsp27 on LPS-induced inflammation and identify the precise mechanisms about how Hsp27 regulates LPS-induced TLR4 signaling in Thp1 cells. Thp1 cells were transfected with Flag-Hsp27 or pcDNA3.1, and then treated with LPS for indicated time. TNF-α, IL-1ß, and IL-6 were determined by ELISA. The protein levels of Hsp27, p-Hsp27 (Ser15, Ser78, and Ser82), and TLR4 were measured by Western blotting. In vitro study showed that over-expression of Hsp27 downregulated the release of TNF-α, IL-1ß, and IL-6 and suppressed the activation of TLR4 signals after stimulated by LPS. The location of TLR4 and RAB5 was detected by confocal microscopy. Immunoprecipitation was used to determine the ubiquitination and degradation of TLR4 and interaction between Hsp27 and TLR4. Results showed that Hsp27 could promote TLR4 endocytosis and ubiquitination and degradation. Further research revealed that Hsp27 was phosphorylated after LPS, only phosphorylated Hsp27 can interact with TLR4 and inhibit the activation of TLR4 signaling, which was demonstrated by inhibition of Hsp27 phosphorylation with inhibitors or transfection of Hsp27 mutants into Thp1 cells. Phosphorylated Hsp27 reduced the release of TNF-α, IL-1ß, and IL-6, and suppressed the activation of TLR4 signaling by promoting TLR4 endocytosis, ubiquitination, and degradation.


Assuntos
Endocitose/efeitos dos fármacos , Proteínas de Choque Térmico HSP27/uso terapêutico , Inflamação/prevenção & controle , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP27/farmacologia , Humanos , Lipopolissacarídeos , Fosforilação , Proteólise , Transdução de Sinais , Transfecção , Ubiquitinação
9.
Mol Immunol ; 108: 45-55, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30780033

RESUMO

Heat-shock protein 27 (Hsp27) is a member of the small heat shock protein family that has been reported to protect cells against pro-inflammatory stresses. High mobility group box 1 (HMGB1) is a proinflammatory cytokine associated with death from sepsis and other inflammatory diseases. After being acetylated by CREB-binding protein (CBP), the transcriptional adaptor and acetyltransferase, HMGB1 translocates from the nucleus to the cytoplasm. In the present study, we investigated the effects of Hsp27 on HMGB1 translocation from the nucleus to the cytoplasm in THP-1 cells. We found that Hsp27 phosphorylation decreased LPS-induced HMGB1 acetylation and translocation from the nucleus to the cytoplasm, as well as its release from THP-1 cells. The study further showed that cytosolic non-phosphorylated Hsp27 enhanced CBP ubiquitination and degradation in LPS-unstimulated cells, which suggested that Hsp27 maintained suitable CBP levels under normal physiological conditions. After LPS stimulation, Hsp27 was phosphorylated at serine residues 15/78 and translocated from the cytoplasm into the nucleus. Consequently, LPS stimulation increased CBP levels and promoted its translocation into the nucleus. In the nucleus, Hsp27 bound to CBP and suppressed CBP acetyltransferase activity and the subsequent CBP-dependent acetylation of HMGB1. Taken together, our data demonstrated that cytosolic non-phosphorylated Hsp27 enhanced the ubiquitin-mediated degradation of CBP, while phosphorylated Hsp27 inhibited CBP acetyltransferase activity in the nucleus. By regulating CBP, Hsp27 maintained cell homeostasis and inhibited excessive inflammatory response.


Assuntos
Proteína de Ligação a CREB/metabolismo , Proteína HMGB1/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Ubiquitinação , Acetilação , Núcleo Celular/metabolismo , Histonas/metabolismo , Humanos , Lipopolissacarídeos , Modelos Biológicos , Fosforilação , Transporte Proteico , Proteólise , Células THP-1 , Ubiquitina/metabolismo
10.
Rice (N Y) ; 8: 18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26029330

RESUMO

BACKGROUND: Rice mutant, spl5 (spotted leaf 5), has spontaneous hypersensitive-like lesions on its leaves and shows enhanced resistance to pathogens, indicating that SPL5 plays a role in programmed cell death (PCD) and disease resistance. To understand the molecular mechanism of SPL5 gene, we investigated the transcriptome profiles of the spl5 mutant leaves with few lesions (FL) and leaves with many lesions (ML) compared to the wild-type (WT) leaves respectively by microarray. RESULTS: The data from microarray revealed that 243 and 896 candidate genes (Fold change ≥ 3.0) were up- or down-regulated in the spl5-FL and spl5-ML, respectively, and a large number of these genes involved in biotic defense responses or reactive oxygen species (ROS) metabolism. Interestingly, according to our microarray and real-time PCR assays, the expressions of a transcription factor OsWRKY14 and genes responsible for the biosynthesis of serotonin, anthranilate synthase (AS), indole-3-glycerolphosphate synthase (IGPS), tryptophan synthase (TS) and tryptophan decarboxylase (TDC) were significantly up-regulated in the spl5 mutant. It has been reported previously that TS and TDC expressions are regulated by OsWRKY14 in rice, which raises the possibility that OsWRKY14 regulates serotonin production through the up-regulation of TS and TDC. Our HPLC analysis further confirmed that serotonin levels were higher in the leaves of spl5 mutant than that in WT. CONCLUSIONS: Since the serotonin plays a critical role in inducing disease-resistance, the increased serotonin level may contribute, at least partly, to the disease resistance in spl5. The SPL5 gene may act as a negative regulatory factor activating the serotonin metabolic pathway, and these results might provide a new insight into the spl5-induced defense response mechanisms in plants.

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